Various underfloor devices are attached to an underframe of a railcar. To attach the underfloor devices, various attaching metal fittings have been used depending on the types of the devices and the types of the railcars. Using such various attaching metal fittings is not preferable in terms of work efficiency and cost. Further, when the underfloor devices are attached to the underframe using fastening members such as bolts, it is desirable to realize such a structure that pulling-direction force for holding the weight of the underfloor devices does not act on the fastening members.
PTL 1proposes such a structure that: a beam member extending in a car longitudinal direction over an entire length of an underframe is newly provided at a car width direction middle of the underframe; and this beam member and side sills support the underfloor devices. According to this configuration, the types of the attaching metal fittings and the number of attaching metal fittings can be reduced, and the pulling-direction force does not act on the fastening members that fix the underfloor devices.